@misc{indiciaec0a2c0ce9f90,
  title = {Ultrahigh Energy Gamma-rays},
  author = {Strong, A. W. and Wdowczyk, J. and Wolfendale, A. W.},
  year = {1973},
  url = {https://ntrs.nasa.gov/citations/19730020034},
  note = {Source identifier: 19730020034}
}